Is Your Checkout Protected From Card Testing?

Card testing can turn small payment attempts into a bigger fraud problem. Fraudsters may use automated attacks to test stolen card information through low-dollar or even $0 transactions before attempting larger purchases.

These attacks can increase declined payments, processing costs, disputes, and friction for legitimate customers.

What Is Card Testing?

Card testing is a type of payment fraud in which criminals use stolen card details to determine whether cards are valid and can be used for future transactions.

Because these attacks are often automated, they can generate large numbers of payment attempts in a short period of time.

Warning Signs of Card Testing

Watch your checkout for unusual patterns, including:

• A sudden increase in declined transactions

• High volumes of low-dollar or $0 authorization attempts

• Multiple retries using slightly different card details

• Repeated activity from the same device, IP address, or location

One indicator alone does not necessarily mean fraud. Multiple unusual patterns occurring together may warrant investigation.

7 Ways to Help Protect Your Checkout

A layered approach can help reduce the risk of automated payment attacks.

1. Verify card details using address and security code checks.

2. Limit payment attempts within a defined period.

3. Monitor device and IP activity for repeated attempts.

4. Use CAPTCHA or additional verification to help block automated activity.

5. Consider customer sign-in instead of allowing unrestricted guest checkout.

6. Block suspicious IP addresses when appropriate.

7. Review declines and disputes regularly to identify unusual trends.

Protect Your Payments With a Layered Approach

Fraud prevention starts with recognizing unusual activity early. Combining transaction monitoring with payment verification, rate limits, authentication, and other security controls can help make your checkout less attractive to fraudsters.

Keep your checkout convenient for legitimate customers while adding meaningful barriers for automated attacks.

[Talk to eMonney About Payment Security →]